Electric-motor controller



Dec. 25 1923; 1,478,713 L.. KEBLER Humam MOTOR coN'rfioLLsH '4 Sheets-Sheet l Dec. 25, maen 1,4'sa,^f1s

L. KEBLER ELECTRIC MOTOR CONTROLLER Filed April l. 1920 4 Sheetsheet 4 saya) /6 @mmm/boz LECKN'ARD KEELER, GE' BE? ELJUE, NEKU YORK, AS 1111313 GQEEL A CQRPOI'LATIQN 'JTSE TO VJARD LEONARD ELEC- INFRV YRK.

CGIQTTEGLLZER.

1335254 fzirial Ho. 379,333.

*mwing a modified connectinn and To 1177 whom. 'Jzf nmg/ f' 'nf-wrn: (i. A f

1 m' :3011 conu'ollmg the startlng resistfs. 1 tn 4 inclusive, the

and Matemted @n a panel 1. A min new g 'the starting resistance, wie fixvd *Una panel having a ing; is a 3 and a. Central core 4,

This iin-m e parts forming the 'iv 'fm' fii-,H an (Ci mnt cni s dan' @ni long.

3,4 The, lower part of the n n' nf dapcnding side rt smft 6 upon Which ef the controller are ntinn is in n shaped sheet; imn pinta 7 Rif Naff /ndmg mars; 8 bent, at ng`1t L. u'e piv *ied nn the :and adjoining the pintas part 'I .hias nn upwariy I), Which located op- 10' of another continuing nbnve the magnet 2 :md panel 1, the pole 10 excnnnected with the rear *he magnet and the pole @f @are of the ate 27 is pivo'ally nsion 9 comes opthe, magnet 11 and nificien curand 2 iewise and. :wave (lt dmn* out-31' pon .mnvabe elements 13 Each nf the Elements ramectivny by a flexi'me 'mis 15 Which form 'the 'receivng a pair of fuses A ren-@wing cfips 17. The :f'ziy @Onnected With ter- Mn* receiving motor connacennnvci' mns:

` mai ..1 n

nun s 13 respectvelj fenn 1.9 which are, shown named :inan the panci l. he :WP eesiirczflj," connected With :E upon shaft 6 is another inwardly @Mending Purs oczated Within the Plates 5. Ai plrefemby a sheet iron plate having an. ofi'set and upwardly extending .part 21' carrying an adjustable screw 22. The body portion of the element 21 when swung inwardly comes opposite the poles of the magnet 2 and is retained as long as sutlicient current fiows in the controlling coil 2. Secured to the face and outwardly extending from the element 21 is a sheet of insulating material 23 lyin in a vertical plane and having pivotally cepending from its outer end a rod 24 having a handle 24'l for manually controlling the movement of the element 21. depending. and inwardly extending portion 25, which, when the element. is in its outer position, makes electrical connection with a yieldably mounted contact 26, mounted on the panel 1 below the controlling coil 2. The element 26 is in electrical connection with a terminal 26' for receiving a connection from the motorl to be controlled. VVhen the element 21 is swung inwardly or held in 'numbered The incoming lines are indicatc'd at 28, the motor armature at 29, series field 30 and shunt field at 31.

lVhen Vit is desired to start the motor, the handle 24' is raised thereby forcing the element 21 inwardly and carrying with it by engagement of the screw 22 on the element 21, the movable contacts 13 so as to cause them to close the main circuit. This enerl gizes the no-voltage coil 11V connected across the circuit, which will hold the armature 9 and element 7 in their inner position and maintain' the motor 'circuit closed. The closing of the breaker will also first interrupt the connection of the part 25 with the contact 26 and cause the energization of the series coil 2, closing-the circuit from one .side of the line through the series coil 2 and a starting resistance 32, thence through the armature 29 to the other side of the circuit.

The closing of the breaker will also cause the'element 21 to be placed in juxtaposition to the poles of the magnet 2 and held in its inner position as longI as suflicient current passes through coil 2.

The motor will thus start with the starting resistanceI 32 in series with the armature and it will be noted that the relationship of the parts is such that the motor circuit canynot be closed for starting the motor without The element 21 also has a.

asrama insuring that the starting resistance is in circuit with the motor armature, because the closing of the breaker necessarily breaks the circuit between contacts 25'and 26.

As the motor comes up to speed and its counter electro-motive-force increases, the starting current Will be gradually reduced to a predetermined amount, at which point the. magnet 2 can no longer'hold the element 21 against gravity or spring pressure and thus permit the element 21 and its controlling handle to fall from the starting position shown in Fig. 3 to the running position shown in F ig- 4. This outward movement of the element 21 will cause contact 25 to engage the fixed contact 26 as shown in Fig. 4 and thus cause th(e starting resistance to be short-circuited as shown in Fig. 5, the contact 25 being electrieally connected to the junction between the series coil 2 and one terminal of the starting resistance. This short circuiting of the resistance then perinits the motor to assume its full speed and automatically establish running conditiens.

'lt will thus be seen that the coil 2 Will automatically permit the starting resistance to be cut out. only after the motor has attained the proper speed and the arniature current reduced to a proper amount to safely permit the short circuiting of the starting resistance. Although the element 21v is thus released by the magnet 2 and permitted to assume the position shown in Fig. 4, the no I voltage magnet 11 continues to hold the ilshaped element 7 and movable contacts 131 in closed position, and will only release these parts upon the failure of the line voltage or its reduction to a predetermined amount. The coil 11 'thus gives automatic protection against no-voltage and the fuses 16 give automatic protection against over-load.

When it is desired to stop the motor, the handle 24' is pulled downwardly or first raised slightly and then snapped downwardly which causes the extensions 27' to engage element 7 and thus pull the armature 9 away from the poles of the magnet 11 and break the main circuit by causing the parts to again assume the position shown in Fig. 2. The opcrative advantages of the controller `will be apparent to those Skilled in the art and it will be seen that the various features of control and protective operation are secured by a'construction of a compact form and which may be economically manufactured.

Fig. 6 indicates the same construction and relationship of parts as above described, except that the coil 2 of the above construction is replaced by a shunt coil 2' connected across the terminals of the starting resistance 32 and has the advantage that in this instance the same form of coil may be used for controlling the starting resistance asis fthe switch element 35) is raised.

ytending flange 48'. shown in its lower position in Fig.

used for the rio-voltage coil lil., lfn the operation is similar to thet s scribed, except that the coil 2' Will he snhjected to a gradually decreasinLMI1 vintage across the starting resistance 32 list ni. otnre speeds up and its counter electroinotire force inci-cases, until finally the roltage across the resistance 32 is so much reduced that the coil 2' Will release the element 21 at a predetermined current and then gerinit the contact 25 to engage the contact; 2G. 'lfhis of coirse short circnits the starting Sistnce 'os before and permits the motor to come up to full speed.

Referring to the ci'nhodiment ot my invention shown in Figs. to 10, the ore shown mountcd upon the panel' and the line terminals :irc shown at 36., The main fixed contacts ot' the controller are indicated at 37 and A pair of contacts 37 ore connected by a inora'ole switch part 33 arrying` nt its opposite ends jvieldable contacts 39' adopted to engage the fixed contacts When Another switch element 40 carries a pair ot j'y'iel-dable contacts 40 Which are adopted to engage and electricnllj.7 connect the pair of c acts 38 When the switch element fit) raised.

Ji magnet having e tio-voltage controlling coil sil is mounted upon the panel and has e U-shaped frame +22 With downcerdly extending legs forming one pole of the net, and a central core 43 having its lower end to form the other pole ot the m'zgnet. The switch element tit) is of magnetic meterial and When raised Will be held in its upper position by the attraction of poles of magnet 41. The switch elemcnts 39 and di) are mechenically connected by sleere 44: passing centrally and freely through 'the core 43 of the magnet, the npper element 39 being shown electrically insuleted from the lower element 40 and sleeve 44 hy :in interposed insnloting dish Another magnet having a, coil 46 Vfor entomatically controlling the circuit the starting resistance ot' the motor is also monnted on the panel below the magnet fi-l e d has a U-shaped magnet frame 4? having parts 4-7' extending toward each other at the lower end of the magnet to form one pole thereot', the other pole of the magnet being formed by the top portion or" the frame 422'. This mognet has an iron plungcr iS in the form of a cylinder Which has a lower ontwerdly ex- This plunger 4.8 is 'l and When raised to its' npper position Within the coil 46 Will be retained there until the current in coil 46 is reduced to a predetermined amount, at which time the plunger will 'fall to its lower position. 'l'hcplunger siti corries o. Conducting platrof) hy means the flange 48', the plate 49 being perfor ted to .receive 'the plunger 48. A spiral 50 is seoted between the Plate 49 and bottom of the nnignet frame 4:? and tends to force the plnnfz'er and plate 4-9' don'nwardly.

in its lower pos ..ion 'the f olr.A .on two contacts shown in the form of pin ol., 51', Which are monnted upon and extent pushcd uim'ardly, this shoulder Will the lower iface ot' the conducting element 40 V and thereby this element and f.-onducting element so :is to cause the contacts carried therehy to the contacts 37, When closing the moto: ircuit. A.

cd beto1 7een the L spiral 5G is seI and the lower upner portion ot' handle of plunger 48. 1uses 1G are shown mounted on the panel. on. opposite sides ti :eo'f end 'ter-ir 'i 58 and. are show et the loi.V the panel for receiving the motor connections.

The electrical connections of this emhodi-a ment of my invention are indicated in Fig. ll, the parts being numbered to correspond With the parts :there described. The incoming lines are connected. to terminals 36, Which are respectively connected to the .lefthand terminals and 38 and When the main circuit is closed the switch elements 39 and 410, the circuitl is continued to the righthand. iii-:ed contacts Bi' and rcspectirely.

made tl'irough the left-hand fuse 16, through the slries controlling' eoil lil-to contact 51' and thence by conducting element. -l-9 or starting resistance 32 to the contact, 51 and thence to terminal. 527., motor orinature 29, series field. 30, terminal :'l, and right-hand fnse 16 to the fixed terminal 37. The shnnt or rio-voltage coil -il is connected across the line to the lower terminals oi' the fuses 16. The shunt field 31 of the motor is similarly connected across the line.

in order .to start. the motor the handle is pushed npwardly, Which raises the rod 53 and presses spring 56 until the plunger -l8 and conducting element are raised from the contacts 51, 51'. against the. pressure of spt-ine' 50. fllaisingrod 53 also causes the shoulder of) to engage the lower face of the comlnct-ing element lil, Which normally rests on top ot' the nmffnet frame 127, and raises the switch elements 4.0 to cause IGG ,ning position as shown in Fig. 10.

the yieidable contacts 'dit'- and to engage the .fixed contacts 371, and 38 respectively. The parts then assume the position' as shown in 8, Which closes the motor circuits and causes the motor to start With the starting resistance 32 in series With the motor armature by reason of the fact that the conducting element 39 is raised from the contacts 51, 51'. The conducting elements 39 and di) Will be retained in their upper position and maintain the circuit closed as long as the line voltage exists or is above a predatermined minimum, by reason of the fact that the poles of the ma net having coil Lil Will hold the magnetic e ement 40 as lon as the rio-voltage coil 41 is suitably excite Liirewise the plunger 48 and conducting lelement 419 Will be retained in their upper positions as long as the series coil 46 carries a current abo've a predetermined value.

After establishing the circuit connections thus described, the handle 52 is released and Will then fall to the position shown in 9 by gravity and pressure of the spring 56, the other parts remaining in their upper positions by the electromagnetic action of the controlling coils lil and 46. I

'The motor vvillgradually increase in speed and the starting current through coil '1) gradually reduced until at a predeteried minimum the spring 50 and gravity will overcome the magnetic attraction of piunger fit; and the latter and conducting el ment 40 Will fall to engage the contacts 51, iii. and short circuit the starting resistance 32, the parts then assuming t e 1%111'1- short-circuiting of the resistance 32 vvili vcause the motor speed to further'increase to the full s eed of the motor.

"W hen it is desired to stop the motor the handle 52 is forcibly pulled downwardly may be slightly raised and snapped downn Wardly, Which Wili cause the nuts 5% on rod 53 engage the insulation 45 and force the two conducting elements 39 and 40 doWn- Wardiy and open the main circuit so that the parts again assume the position shown in 7. The motor may be started again by raising the handle 52 and it Will be noted that the construction is such that the motor circuits cannot be closed Without first inv ciuding the starting resistance 32 in the motor armature circuit. lt is also evident that this construction secures a compact and tamara economically manufactured apparatus, the protection of the motor circuits against novoltage and over-load, as Well as insuring the proper starting of the motor.

In Fig. 12 the diagram indicates the same construction and connections of the parts, except that the series coil 46 is replaced by a shunt coil connected across the starting resistance 32. The operation and controlling action of the device Will then be the same as alread described, excepting that the release of tie plunger 48 and conclucting element 49 Will be dependent upon the reduction to a predetermined minimum of the voltage across the starting resistance as the motor speeds up, instead of upon the reduction of the starting current to a predetermined value.

Although I have described particular embodiments of my invention, it Will be understood that various modifications and exemplifications of my invention may be made without departing from the scope thereof.

l. In an electric motor controller, a main switch, a starting resistance, a magnet for.

holding said main switch in closed position, a switch for normally short'circuiting'said resistance, a manually movable device whereby said second named switch may be 'manually opened and the main switch manually closed, and electromagnetic means for automatically ca using the closure of said second named switch to short-circuit said resistance When the motor attains proper speed, andmeans controlled by the movement of said device V whereby the main switch maybe manually opened.

2. In an electric motor controller, a main I switch, a starting resistance, a switch for normally rendering said resistance melfectit/e, a manually movable element for causing the movement of said second switch to render said resistance effective and for causing the main switch to be closed, a no-voltage magnet for retaining said main switch in closed position, and a second magnet for causing the movement of said second switch to render said resistance ineffective When the motor attains proper speed, said ,lement having means for causing the maniuiil opening of said main switch upon movement of said element in a direction opposite to that for closing the main switch.

LEONARD KEBLER. 

